The present invention relates to improvements in construction modules, to building constructions utilizing such modules, and to improved methods for erecting buildings employing such construction modules.
In sharp contrast to the rapidly developing technology in many other fields, construction technology has-proceeded at a relatively slow pace over the last half-century. Although numerous techniques have been developed, these have not been adopted widely by the construction industry with the result that construction has remained labor intensive and of a handicraft nature. Accordingly, housing and building costs have remained very high.
Prefabrication has been cited as one of the potential answers to the problem, but many of the proposals to date have not proven to be commercially successful and relatively few prefabrication techniques have been adopted by the industry. Prefabrication techniques fall under two major categories, namely, light wood and aluminum frame prefabrication, and concrete or like product precasting. Wood and aluminum frame prefabrication is limited to low density suburban housing. Concrete prefabrication is more appropriate for urban buildings due to fire and structural safety requirements.
The majority of the concrete precasting prefabrication systems, many of which were designed in Europe, have not been commercially successful, particularly in North America. Most are structural systems and not housing or building systems. While structural i.e. walls, floors, they do not incorporate functional attributes related to housing building users"" needs and architectural understanding. In addition to not being user or market oriented to any substantial degree, these known systems tend to be costly, requiring expensive prefabrication factories and relatively expensive handling and erection equipment and techniques. To be viable such concepts usually require a very high degree of repetition.
Most of the prior art concrete prefabrication systems follow one of three primary conceptual types, namely:
(1) a shear wall and floor plate design; primarily high rise, with the innovative part of the design being concentrated around the connection details. Erection usually requires shoring and bracing. These systems tend to produce a heavy structural box which has no particular relationship to any specific end use. These structures require finishing, further partitioning and outfitting with traditional add-on methods and equipment.
(2) a three-dimensional concrete box; like the shear wall system noted above, the use of the space within such stacked boxes is arbitrary and the end use and function has to be created by an add-on system of traditional finishes, partitions and equipment.
(3) on site systems of either large, portable forms for pouring in place, or wire cages and walls with the concrete sprayed on and then trowelled on-site. These systems do not require expensive factories and handling equipment; however, they do require skilled on-site labor and the system is capable of providing only the macro-space. All finishes and equipment must then be added in the traditional fashion.
A variety of patents have issued over the years relating to various types of prefabricated units or slabs intended to be assembled into a building or other structure. One common problem which remained largely unsolved was that they were closed systems with limited architectural flexibility and space flexibility.
Another form of building construction is a variation of type (1) above and involves the use of shear walls of shallow U-shaped cross-section. Examples of patented processes and construction module configurations of this type are described in U.S. Pat. Nos. 3,952,471 to Mooney, and 4,142,340 to Howard. The Mooney patent essentially discloses a building structure having a series of vertical precast combination foundation wall and side wall panels of shallow U-cross section supported on a footing at spaced apart intervals. This structure includes in-fill panels with cast-in windows and doors. The in-fill panels are connected by welding between load-bearing vertical side edge flanges of the wall panels. This system provides only an exterior wall arrangement.
The building construction scheme described in the Howard patent employs a series of standard panels each having a shallow U-shape cross-section. The walls are formed by a series of such panels disposed vertically in side-by-side relationship. Because of their instability, as is the case of the Mooney panels, the panels must be temporarily braced during erection and then permanently connected to each other by fastener elements. In the Howard scheme, a plurality of side fastener elements which bridge the panels are employed. In essence, the Howard configuration involves an exterior wall system which works in conjunction with a predetermined roof system. A somewhat specialized footing is also required to provide for connection to the vertical exterior wall panels. In the construction arrangements described by both Howard and Mooney, neither module performs a volumetric, space enclosing function related to architectural requirements.
One object of the invention is to provide an improved building module which acts as a functional container responding to the users"" functional requirements, which module allows the creation of custom designed solutions, which module is self-standing or self-supporting and can be readily provided with an internal power and/or communications network.
Another object of the invention is to provided an improved modular construction in which the basic modular unit is in the form of a U-shaped channel whose shape and proportion provides a multi-purpose functional container for enclosing housing or building users"" appurtenances and facilities. It is a further object to provide a module which is structural (load bearing), and can be arranged to provide structural exterior and interior bearing walls as well as interior partitions.
The present invention provides a universal building construction module in the form of an elongated deep U-shape formed of a rear wall and two side walls, the module being one story in height when disposed end down on a concrete slab, the real wall of the module being sufficiently wide to span the major portion of a room, the width of the side walls of the module being sufficient with the rear wall to enclose on three sides and define the walls of a standard facility within the room while at the same time the side walls of said module form supports for the rear wall sufficient to cause the module to be free standing while devoid of lateral support.
The present invention also provides a building comprised of at least one room, the room having concrete walls formed of precast universal building construction modules each being in the form of an elongated deep U-shaped formed of a rear wall and two side walls, the modules being one story in eight and disposed end down on a concrete slab, the rear wall of at least one module being sufficiently wide to span the major portion of a room, the width of the side walls of each module being sufficient with the rear wall to enclose with three sides and define the walls of a standard facility within the room while at the same time the side walls of said modules form supports for the rear walls sufficient to cause the modules to be free standing, the modules also being devoid of mutual lateral support, and a roof element supported by said free standing building modules. The building can be of size from a single one room hut to a multi-story highrise. All use the same basic modules described herein.
The expression xe2x80x9cstandard facilityxe2x80x9d as employed herein is intended to include any of the standard appurtenances commonly used in residential building construction, including: kitchen counters, cupboards and appliances, bathroom counters, bathtubs, shower stalls, closets, fireplaces and the like.
The expression xe2x80x9cmodulexe2x80x9d as employed herein is also intended to include the case in which two U-shaped structures are located back-to-back and cast as a single unit, or two U-shaped structures of the kind described with a common rear wall.
Preferably the module contains an internal conduit system providing for multiple access points for junction boxes, electrical switches or electrical or other outlets at the major surfaces of the flanges and/or the major surfaces of the main panel of the module, with the distribution being so arranged as to allow electrical and telephone and/or cable and/or intercom to be wired in the module. The module may have a raceway, trough or groove cast in its top end to allow the connection of power or communication sources within the module and to allow module-to-module electrical or communications connections.
Preferred embodiments of the invention provide a flexible form of modular building construction which allows custom design solutions for a wide variety of building types either single, low or medium rise. The modules are small in size thus resulting in efficiency and economies in casting, transporting, erecting and connecting because of the elimination of the need for large or special factory or handling equipment. The self-standing modules can be erected quickly and directly and can incorporate levelling and centering means which may be positioned prior to placement of the modules thereby to further accelerate the building erection process and to provide accuracy of the placement of the modules.
Preferably the modular building system is an open system. It allows the use of the builders"" choice of local standard windows, doors, roofs and other equipment. These local standard windows and doors are preferably set between the modules, although they can, if desired, be cast in the modules. Windows and doors set adjacent to the modules provide the advantage of connecting them to the modules on-site using standard connection details and further-to provide the construction tolerances required. Moreover, the connection of building modules to each other, to floors and roofs, also requires only the use of standard on-site connection details and local practices.
The modules are designed to be of sufficient depth to define multi-purpose functional containers capable of enclosing or delineating kitchens, bathrooms, closets, fireplaces, bookshelves, buffets, etc., rooms of domestic proportions or any other appurtenances and facilities, in housing or filing, machines, storage retail shelving and show space for offices and retail buildings.
Preferably the module is of a height which is a multiple of the normal floor to ceiling height: of residential and building constructions. In multi-story applications, such modules retain their structural, self-supporting and self-standing capabilities while serving as full height exterior wall systems or as interior wall systems of a demising nature. Such modules for multi-story applications desirably have the capability of using normal concrete inserts to support floors of prestressed/precast slabs, or floors of a wood or steel structure.
The modules can be made with final finished surface. The modules are cast in a single process. Normally, they are cast in an open steel mold, vibrated, and the non-formed surfaces trowelled. This produces a high quality final finish on all surfaces. The modules are thus ready for paint or wallpaper without further finishing. This eliminates the need for furring, gyprock, taping of gyprock joints or any other secondary wall surfacing. The modules have the above-noted electrical and communications conduits cast into them during this single process. The result is a module with finished walls with built-in infrastructure. The module may be cast in room heights of 8 feet or multiples thereof. Its"" small size results in economy in casting, demolding, handling transportation and erecting. Moreover, its small size allows flexibility in design manipulation.
The number of sizes of modules required for maximum flexibility is small. The module can be of a greater number of sizes, these sizes dictated by its functional characteristics of responding to the user, being structural or load bearing and self-supporting. However, it has been found that 3 to 5 sizes of modules are required for wide flexibility of design. Where required, L-shaped modules can be made simply by blocking off a portion of the mold for a U-shaped module.
Previously, it was indicated that the modules"" unique shape results in a self-standing or self-supporting characteristics. This allows the modules to be erected without scaffolds, shoring, etc. This characteristic is accentuated through the use of the above-noted levelling and centering means which facilitates quick and easy on-site erection. The bottom of a typical module is provided with bearing pads which mate with the centering and levelling means which are installed on the floor prior to the modules being erected. This system eliminates the need to constantly lift and adjust the module vertically and horizontally during erection. Rather the module can be lowered downwardly and positioned true and level in a single motion. Therefore, the erection process is significantly speeded up, and costly crane and equipment staff are utilized more efficiently. The need for skilled labor is greatly reduced as compared with traditional methods, this being a great advantage in regions where there is a shortage of skilled labor or where labor costs are exceedingly high.